Hello guys,

Iam posting this for my friend as he is working nights this week. He has a 93 FD we just got running yesterday. He drove the car today and all is good with normal driving and idling and so on. As you go full throttle and get into boost just as the car starts to "go" it backfires real loud and falls on its face at the same time. The car is bone stock with a hks downpipe and no other exhaust as he was driving to the muffler shop. I havent heard from him since the muffler shop so I will ask him if that changed anything. Thanks in advance for your help.

 

What about if you do ANY boost? Is it the same? or only full throttle?

 

part throttle boost is ok to an extent didnt rev it all the way, but the more throttle you give it the sooner the cut comes. Problem seemed to get a little better after putting a midpipe on the car.